The detection and measurement of gas concentrations is important for both the understanding and monitoring of a wide variety of applications, such as environmental monitoring, industrial process control analysis, combustion processes, detection of toxic and flammable gases, as well as explosives. For example, gas sensors capable of high sensitivity and selectivity can be used in atmospheric science for the detecting and monitoring of different gas species including greenhouse gases and ozone, and in breath diagnostics, for detection and monitoring of nitric oxide, ethane, ammonia and numerous other biomarkers. As another example, in gas-to-grid applications, methane generated from a bio process is tested for impurities (e.g., hydrogen sulfide or H2S) to determine whether the methane is pure enough to be mixed directly with natural gas.